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By Peter Rejcek
The International Polar Year (IPY) officially came to
an end in March. But the legacy of the two-year campaign
to learn more about the world’s polar regions will
likely last far into the future.
IPY scientists accomplished a dizzying amount of work
in the Antarctic and Arctic — from mapping rugged
mountain ranges buried hundreds of meters below the ice
cap to making underwater observations below an ice shelf.
They crisscrossed Antarctica on ski-equipped airplanes
and on tracked vehicles. Ice-strengthened ships carried
them to little-visited corners of the Southern Ocean,
discovering new species in the frigid waters.
The effort involved more than 60 countries and 10,000
scientists, including many funded by the National Science
Foundation (NSF) , which manages the U.S. Antarctic Program
(USAP) .
“The glimpses I’ve had of the data sets from
this season and last year are astounding. I’m very
pleased with our investments in IPY,” said Antarctic
Sciences Division Director Scott Borg in the NSF’s
Office of Polar Programs .
Launched in March 2007, the IPY actually spanned a two-year
period to encompass seasonal research in both polar regions.
Several of the larger Antarctic projects will continue
for several more years.
One such project is ICECAP, for Investigating the Cryospheric
Evolution of the Central Antarctic Plate , which just
completed the first of three field seasons.
ICECAP researchers used a converted World War II-era
DC-3 aircraft, outfitted with a suite of geophysical instruments,
to fly over a region of East Antarctica to measure the
thickness of the ice sheet and the texture, composition,
density and topography of the bedrock below the ice.
The scientists — representing the United States,
the U.K. and Australia — believe two subglacial basins
that sit well below sea level, but hidden by the ice,
could help speed the flow of ice into the ocean, raising
sea level. Funding for the project came from NSF, the
U.K. Natural Environment Research Council , the Australian
Antarctic Division and the University of Texas . The researchers
will use both U.S. and Australian facilities for the experiment.
“This is a real IPY project, where everybody is
chipping a lot in,” noted Don Blankenship, a research
scientist at the Jackson School’s Institute for Geophysics
at the University of Texas at Austin and ICECAP principal
investigator.
Another IPY project, Antarctica’s Gamburtsev Province
(AGAP) , also used aircraft to survey East Antarctica
and the bedrock below its icecap, but focused on a ragged
mountain range buried in the ice that was first discovered
more than 50 years ago during the International Geophysical
Year (IGY) , a predecessor to the IPY. The project also
used seismometers to image the area.
The sharp peaks showing in the raw data suggest the East
Antarctic Ice Sheet formed quickly, because the slow grind
of glacial movement didn’t wear down the mountains
into a plateau.
“People will be digesting those data and interpreting
them for quite a while,” Borg said. “We can
look forward, in the next year or two, to a lot of papers
describing the data, and more importantly, inferring things
about the subglacial continent and the ice sheet.
“The AGAP and ICECAP projects are going to give
us some very fundamental information about the continental
surface beneath the ice cap. … Those are data sets
that will be mined for decades into the future,”
he added.
The aerial surveys by both projects should also help
scientists locate the continent’s oldest ice, estimated
to be more than 1 million years old. The oldest ice core
recovered to date is about 800,000 years old, coming from
the European Program for Ice Coring in Antarctica (EPICA)
project conducted earlier this decade.
One-million-year-old ice isn’t just a big number.
It represents a time when the duration of glacial cycles
more than doubled. Some time before 1 million years, ice
ages waxed and waned on a 41,000-year cycle. Now, it’s
a 100,000-year cycle. Understanding what flipped the switch
is important for climate change researchers trying to
model the pull-and-tug between temperature and greenhouse
gases.
“That’s why people are interested in getting
a hold of this old ice,” Borg said. “The radar
data sets will define areas where there is likelihood
[of old ice].”
IPY made large-scale, deep-field projects possible
The World Meteorological Organization (WMO) and the International
Council for Science (ICSU) hosted the first effort to
synthesize the findings from the IPY effort, estimated
at more than $1.2 billion from all participating nations.
In a “State of Polar Research,” a report released
in Geneva at the end of February by a joint IPY committee
of the WMO and ICSU, scientists reported the effects of
global warming on both poles.
The 16-page report said: “New assessments of the
state of the Greenland and Antarctic ice sheets have been
made using novel techniques. These include satellite measurements
of changes to the elevation and the gravitational fields
of the ice sheets. … These assessments continue to
be refined, but it now appears certain that both the Greenland
and the Antarctic ice sheets are losing mass and thus
raising sea level, and that the rate of ice loss from
Greenland is growing.”
The ocean appears to play an active role in ice melt.
A project led by Stan Jacobs , with Lamont-Doherty Earth
Observatory at Columbia University , aboard the USAP’s
RVIB Nathaniel B. Palmer , is monitoring the incursion
of slightly warmer water onto the continental shelf in
an area of West Antarctica called Pine Island Bay —
home to one of the continent’s fastest moving glaciers.
The ocean-ice shelf interaction is another important
variable as the science community attempts to calculate
sea-level rise, with recent reports estimating a one meter
increase by century’s end.
“My expectation is that this cruise collected a
lot of data to advance understanding of that process,
but I haven’t seen the data sets yet,” Borg
said.
One expectation is that the spirit of IPY — the
broad international cooperation it fostered — will
live well past this month. In light of the current global
recession and the increasing cost and scope of polar research,
it seems collaboration between nations must continue.
That’s the conclusion Tom Neumann, expedition leader
of the second leg of a joint Norwegian-U.S. IPY Traverse
across East Antarctica, made after the team completed
the nearly 5,000-kilometer-long overland journey to study
climate variability.
“This project has been carried out in the true spirit
of the International Polar Year,” Neumann wrote on
the expedition’s Web site dated Feb. 23. “Neither
the U.S. nor Norway could have completed this project,
either scientifically or logistically, on their own. Our
collaboration has been the key feature of this project.”
Ted Scambos , lead scientist at the Boulder, Colo.-based
National Snow and Ice Data Center and member of the Norwegian-U.S.
IPY Traverse, said the new level of cooperation led to
unprecedented scientific advances in East Antarctica.
“I think one of the main legacies of IPY is that
it really opened up East Antarctica. We knew some things
about East Antarctica from [the IGY], the earlier traverses
through the 1960s, but we didn’t know a whole lot.”
The Norwegian-U.S. IPY Traverse, for instance, will add
new details to the climate record of East Antarctica from
the last millennium. The traverse scientists also mapped
out a region of subglacial lakes called the Recovery Lakes.
And AGAP, ICECAP and other projects all contributed to
a more robust understanding of East Antarctica, which
contains enough ice to raise sea level by 60 meters should
it all melt. (An unlikely scenario for thousands of years.)
“All of that puts East Antarctica into the same
league as West Antarctica in terms of understanding what
kind of player it is in the ocean-ice system,” Scambos
said.
Borg said he anticipated more logistically challenging
projects in the future, but said the NSF had not funded
anything specific at this time. “We do have active
interest in collaborating in new ice-coring sites in the
near future,” he said. “And I’m sure things
like AGAP will come along in future.”
The report from the WMO and ICSU stressed the need for
further research into the Antarctic and Arctic, based
on the findings from IPY.
“The polar regions are an integral and rapidly changing
part of the Earth system. Humankind’s future environment,
well-being and sustainable development require that we
comprehensively understand and observe polar systems and
processes and the changes that are already upon us,”
the report concluded. “The message of IPY is loud
and clear: what happens in the polar regions affects the
rest of the world and concerns us all.”
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